From 087105d1f31d83ff88ceeca30dfe36dc01de28d7 Mon Sep 17 00:00:00 2001
From: Giulio rebuffo <giulio.rebuffo@gmail.com>
Date: Thu, 30 Jun 2022 18:20:21 +0200
Subject: [PATCH] lvh on invalid transition block (#4583)

---
 eth/stagedsync/stage_headers.go             |  4 ++--
 turbo/stages/headerdownload/header_algos.go | 15 ++++++++++++---
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/eth/stagedsync/stage_headers.go b/eth/stagedsync/stage_headers.go
index cebd06e98a9..4aefc5079e6 100644
--- a/eth/stagedsync/stage_headers.go
+++ b/eth/stagedsync/stage_headers.go
@@ -585,7 +585,7 @@ func verifyAndSaveNewPoSHeader(
 		// TODO(yperbasis): considered non-canonical because some missing headers were downloaded but not canonized
 		// Or it's not a problem because forkChoice is updated frequently?
 		if cfg.memoryOverlay {
-			status, latestValidHash, validationError, criticalError := cfg.hd.ValidatePayload(tx, header, body, false, cfg.execPayload)
+			status, latestValidHash, validationError, criticalError := cfg.hd.ValidatePayload(tx, header, body, cfg.chainConfig.TerminalTotalDifficulty, false, cfg.execPayload)
 			if criticalError != nil {
 				return &privateapi.PayloadStatus{CriticalError: criticalError}, false, criticalError
 			}
@@ -601,7 +601,7 @@ func verifyAndSaveNewPoSHeader(
 	}
 
 	if cfg.memoryOverlay && (cfg.hd.GetNextForkHash() == (common.Hash{}) || header.ParentHash == cfg.hd.GetNextForkHash()) {
-		status, latestValidHash, validationError, criticalError := cfg.hd.ValidatePayload(tx, header, body, true, cfg.execPayload)
+		status, latestValidHash, validationError, criticalError := cfg.hd.ValidatePayload(tx, header, body, cfg.chainConfig.TerminalTotalDifficulty, true, cfg.execPayload)
 		if criticalError != nil {
 			return &privateapi.PayloadStatus{CriticalError: criticalError}, false, criticalError
 		}
diff --git a/turbo/stages/headerdownload/header_algos.go b/turbo/stages/headerdownload/header_algos.go
index 759ba81be44..1aabb1e3f00 100644
--- a/turbo/stages/headerdownload/header_algos.go
+++ b/turbo/stages/headerdownload/header_algos.go
@@ -1093,7 +1093,7 @@ func abs64(n int64) uint64 {
 	return uint64(n)
 }
 
-func (hd *HeaderDownload) ValidatePayload(tx kv.RwTx, header *types.Header, body *types.RawBody, store bool, execPayload func(kv.RwTx, *types.Header, *types.RawBody, uint64, []*types.Header, []*types.RawBody) error) (status remote.EngineStatus, latestValidHash common.Hash, validationError error, criticalError error) {
+func (hd *HeaderDownload) ValidatePayload(tx kv.RwTx, header *types.Header, body *types.RawBody, terminalTotalDifficulty *big.Int, store bool, execPayload func(kv.RwTx, *types.Header, *types.RawBody, uint64, []*types.Header, []*types.RawBody) error) (status remote.EngineStatus, latestValidHash common.Hash, validationError error, criticalError error) {
 	hd.lock.Lock()
 	defer hd.lock.Unlock()
 	maxDepth := uint64(16)
@@ -1103,6 +1103,11 @@ func (hd *HeaderDownload) ValidatePayload(tx kv.RwTx, header *types.Header, body
 		criticalError = fmt.Errorf("could not read block number.")
 		return
 	}
+
+	isAncestorPosBlock, criticalError := rawdb.Transitioned(tx, header.Number.Uint64()-1, terminalTotalDifficulty)
+	if criticalError != nil {
+		return
+	}
 	if store {
 		// If it is a continuation of the canonical chain we can stack it up.
 		if hd.nextForkState == nil {
@@ -1115,7 +1120,9 @@ func (hd *HeaderDownload) ValidatePayload(tx kv.RwTx, header *types.Header, body
 		validationError = execPayload(hd.nextForkState, header, body, 0, nil, nil)
 		if validationError != nil {
 			status = remote.EngineStatus_INVALID
-			latestValidHash = header.ParentHash
+			if isAncestorPosBlock {
+				latestValidHash = header.ParentHash
+			}
 			return
 		}
 		status = remote.EngineStatus_VALID
@@ -1165,7 +1172,9 @@ func (hd *HeaderDownload) ValidatePayload(tx kv.RwTx, header *types.Header, body
 	validationError = execPayload(batch, header, body, unwindPoint, headersChain, bodiesChain)
 	latestValidHash = header.Hash()
 	if validationError != nil {
-		latestValidHash = header.ParentHash
+		if isAncestorPosBlock {
+			latestValidHash = header.ParentHash
+		}
 		status = remote.EngineStatus_INVALID
 	}
 	// After the we finished executing, we clean up old forks